Hey guys, I have been stuck for days on trying to call a simple contract from a React Dapp using Metamask and Ganache. Is there anyone here that would be willing to have a look at my code for a second and enlighten me?

Mar 10, 2020, 10:16 AM

Check the dapp university tutorial called marketplace

Or read the drizzle docs

Mar 10, 2020, 10:17 AM

Thanks I’ll look into it

Is there any quick way in the JS console to check whether my Dapp is finding the web3 injected by Metamask?

When I type web3.window in the console it says:

inpage.js:1 MetaMask: web3 will be deprecated in the near future in favor of the ethereumProvider

Mar 10, 2020, 10:21 AM

Check the web3 docs.

You should correctly setup the blockchain provider, then get the network and finally create the instance of your contract

Mar 10, 2020, 10:24 AM

Yeah my metamask and ganache are set up properly

Too bad it’s not real ETH

Mar 10, 2020, 10:28 AM

This might be your solution

https://medium.com/metamask/https-medium-com-metamask-breaking-change-injecting-web3-7722797916a8

Basically you need to enable metamask explicitly by

await ethereum.enable();

If not, you might wanna share some code snippet

Mar 10, 2020, 10:30 AM

Post code snippet

Mar 10, 2020, 10:36 AM

Hmm I thought this change hadn’t been implemented yet?

Currently my index.js file only contains the following:

var Web3 = require('web3');

console.log(Web3.window);

Mar 10, 2020, 10:41 AM

It has been, for a long time it's live

The other changes were canceled but not this one

Mar 10, 2020, 10:42 AM

When I run it my console says: undefined

Mar 10, 2020, 10:42 AM

Pretty sure it's window.web3

Not the other way around

Mar 10, 2020, 10:43 AM

Oh that actually works, cool

Mar 10, 2020, 10:43 AM

Window is the default config object of browser's DOM where metamask injects web3

Thanks for confirming

For other curious fellas, metamask team wanted to remove automatic state change triggers from the extension but canceled because it would have caused lot of breaking changes

Mar 10, 2020, 10:46 AM

I’m trying this out right now, but before I move on — how do you insert these nice code snippets in Telegram?

Mar 10, 2020, 10:59 AM

embed in `

We have the entire markdown support here

https://sourceforge.net/p/telegram/wiki/markdown_syntax/

Mar 10, 2020, 11:02 AM

like this?

sweeeet

Mar 10, 2020, 11:05 AM